Changing Our Classroom: Starting Monday, the classroom for parallel pedagogy is now 53-213. Thus, the noon class (141-08) will remain in this classroom. Then Professor Klay will be in that room at 1:00 PM, and our 2:00 class (141-10) will NOT be in 206, but will be in 53-213. See you there!

How is the structure of our course working for you? Are you pacing yourself and setting aside learning time every day? If you are feeling resistant to the learning model, come and talk to me. We want to make it work for you.

This week we will bring all the concepts together in a summary of the four lenses. We will begin attacking open-ended problems using our tools and develop a sense for how one quantity scales with changes to its components. We will learn how to calculate power, how to collect and analyze motion data, and map out our first video projects.

Learning Outcomes

By the end of this week you will be able to:

Use and explain all four lenses of mechanics
Describe how scaling affects various quantities
Explain the difference between constant and conserved
Find position and acceleration vs. time from velocity vs. time graphs
Collect and analyze useful video data of objects in motion
Develop a physical model for a powerful situation

Day 5 | Monday 1/10 | Lens Application, Scaling

Chapter 1.8 is probably the MOST IMPORTANT SECTION in the textbook. please read through and in the future, refer back to this roadmap for addressing questions. Put the important ideas on your idea sheet.

You've probably heard of Elon Musk, right? He earned undergraduate degrees in physics and economics. I'm not a big fan of his business practices, but the article in today's reading gives some insight into his approach to engineering by simplifying problems with scaling. Even though the chapter on scaling might seem boring, it underpins so much about our society, science, and biology... what do you think?

I graded the discussion for week 1. For 4/4, I expect to see daily reflections on the readings and a response to others' responses. It's not a must everyday to have both, but that would be great. I encourage you also to ask/talk about other aspects of the class, but please make sure to post statements about the readings.

Goals:

By the end of the today you will be able to...

Articulate a justification for which lens to use
Explain how changing one aspect of a scenario (like size, density, speed, force) changes something else (like mass, momentum, energy)
Practice using multiple lenses on a given problem
Identify the source of "hidden" momentum

Before Class:

Video: Watch Applying the Four Lenses [10m21s]
Textbook: Read Ch 1.8 - Applying the Four Lenses [3 pg, 3 ex]
Textbook: Read Ch 1.9 - Scaling [1 pg, 4 ex]
Article: Read about how Elon Musk's companies use scaling.
Discussion: Please leave a statement or question on our Week 2 Reading Discussion
Video: Watch Metric System and Scaling [9m56s]
Reflect: on our roller coaster demo from last week. If you think your old model was incorrect, please develop a new model to explain what you think we will see.

During Class:

We will consider some scaling scenarios.
We will explore the rollercoaster demo through the momentum lens.
We will consider where momentum comes from.
We will discuss conserved vs. constant quantities.

Day 6 | Tuesday 1/11 | Forces, Work, and Power

You will be doing a video analysis to estimate the acceleration of a grasshopper. There are multiple ways to do this. One way is with the free software tool Tracker. It is available for download and as an online web-based tool. We recommend you give it 10-20 minutes, but if you can't make it work, move on and come up with another method. Maybe discuss with your group and work together. In the face of fighting with malicious software, you need good friends. All the same, if Tracker doesn't work for you, please do your best to estimate the acceleration any way you can.

Goals:

By the end of today you will be able to...

Distinguish Power from Work and Energy: Work is an exchange of energy. Power is the rate of that work.
Analyze the motion of an object through video and image analysis
Articulate why learning is hard and how to recognize when we are learning.

Before Class:

HEY!... Do you know my office hours? They are MTWR at 1:00 PM and Wednesday at 11:00 at the entrance to building 53.
Homework: Upload Problem Set #2 to Canvas before class.
Video: Watch Energy, Work, and Power [3m33s]
Textbook: Read Ch 2.0 - Work[1 pg, 2 ex]
Textbook: Read Ch 2.1 - Power [2 pg, 5 ex]
Article: Read NPR: Confusion is How it Feels to Learn (external link)
Discussion: Please leave a statement or question on our Week 2 Reading Discussion
Video: Watch Veritasium: The Science of Thinking [12m9s]
Video: Watch Smarter Everyday Grasshopper[4m1s]
Analysis: Use the Tracker software or another method of your choice to repeat Dustin's experiment with the other grasshopper:. (right-click to download). For our in-class meeting, be prepared to discuss how you estimated acceleration.
Problem-solving: Also be prepared to answer this question: a 1000 kg car starts from rest and accelerates to 30 m/s in 5 s. Please calculate the average power the car produces to do this, expressing your answer in both Watts and Horsepower.

During Class:

We will discuss the power of an accelerating car.
We will review Tracker.
We will use still images to analyze acceleration.
We will discuss different levels of thinking and what it feels like to learn.

Day 7 | Wednesday 1/12 | Units and Graphing Kinematics

We are learning to recognize the relationships between position, velocity, and acceleration by interpreting graphs and getting ready for our video project by practicing using the video and analysis tools (e.g. Tracker and Excel) we will need for the projects. If you didn't use Tracker for yesterday's preparation, try it now. Make sure you can make it work, or come in with a question. The documentation on the Tracker website (including videos), instructions and Smarter Everyday Video from yesterday can help. One suggestion is to use Tracker to extract the data and then export it to a file and use Excel, as shown in Pete's video for the analysis.

Goals:

By the end of the today you will be able to...

Explain why it is important to carry units through calculations
Use Tracker to process videos of motion into x, v, t data
Use Tracker or Excel to analyze x, v, t data
Create graphs of x vs t and a vs t from v vs t graphs
Practice applying the lens method on a novel problem

Before Class:

Video: Watch How We Grade Assessments [1m14s]
Textbook: Read Ch 2.2 - Units [1 pg, 1 ex]
Textbook: Read Ch 2.3 - Graphical Analysis of Motion [1 pg, 1 ex]
Discussion: Please leave a statement or question on our Week 2 Reading Discussion.
Video: Watch Graphing Kinematics LIVE! [7m54s]
Action: Please make a video of yourself/your friend/your dog, etc. accelerating. Make graphs of position, velocity, acceleration as functions of time. You may notice that the acceleration is very noisy... how can you reduce this noise? This is part of Problem Set #3, but will also ultimately be part of the group project. Feel free to use any spreadsheet program that you like such as Excel or Google Spreadsheets
Study: We will have our weekly assessment in class. Review what you have learned so far and look at the solutions to Problem Set #2 to see how to improve. Follow the problem-solving rubric and the video above so you are prepared to answer the question.
I posted solutions to PS #2. Understanding PS#2 would do well to prepare you for assessment #2.
Thursday, we will have class on Via Carta Street at the bottom of Baker Science. You will have 3-4 students in the group. We will read about the project details for tomorrow's class, but if you like, have a look now at the video project so you have an idea of what it is.

During Class:

We will discuss the importance of units
We will review how assessments are graded
We will create motion narratives for graphs
We will take Weekly Assessment #2 [10 min]
We will find and graphs from graphs

Day 8 | Thursday 1/13 | Power Production Activity

Today we will be doing our video analysis data collection outside (weather permitting). Meet in the classroom and we will proceed together to Via Carta. Be prepared to take videos of you and your teammates doing something powerful. If you have a bike or a skateboard, you might consider bringing it.

Downloading a Tracker that Works! It turns out that there's an old version 5.1.5 available at this website. But there's more: After you load your file, you hit "create" and create a point mass. Then you have to control+shift click to mark the spot you want to track. Then the search box should pop up to the right. Click "search" to let it go, or "search next" to let it auto track frame by frame. Anyway, that's how I got it to work for me... at 1 AM.

Goals:

By the end of the today you will be able to...

Collect motion data for a video analysis project
Develop a plan for your video project with your group mates

Before Class:

The first video for today is the final project from a past group of students. You might get some useful ideas from it.

Video: Watch Horsepower of a Horse [4m26s]
Video: Watch Analyzing Motion with Excel [9m28s]
Video: Watch Grasshopper Kinematics [4m11s]
Canvas: Read the Project #1 Description to prepare for your activity. How are you going to show someone in your group exerting themselves, putting out power?
Please thoroughly read up about the video project that we will do together in Thursday's class. How to make Tracker work? They've changed Tracker since last quarter, and now there is no auto tracking feature, AND it's harder to upload a video file:
1. you have to search for your desktop... you may find this under "user" in the menu.
2. You have to set each data point as the video moves. You need to do a "shift-click" in order to make one data point. When you do this, the video will advance to the next frame. Then you can shift-click on the next frame, etc. It's described in this instructional video at 10:50.
Discussion: Please leave a statement or question on our Week 2 Reading Discussion. Maybe ask for advice on project ideas?
Survey: Take Short Survey Day 8 [4 questions]
Hey, so your assessment? This is a famous question. It's been studied and published about by many people... including us! Please have a look at our publication of students solving this problem. You might just read the conclusion if you don't have a lot of time. The average grade is about a "D", so it seems the assessment was overly ambitious. It's OK. If you read the publication, you find that only ~ 25% of the people got these questions right... at the end of the course. So, I invite you to please consider the questions again: Consider a lens with the motivation. Please write up an idea sheet. I recommend something expressing the important 4 statements from Chapter 1.8... hand written. Future assessments won't be so ambitious. But they will require you to identify, motivate, and follow a lens. Curious? Please see past assessments... links to past classes are on Canvas Homepage.... The most universal thing that folks did wrong was that you tried to answer the question in the first sentence. That is not possible for these questions... and most questions. You really need to ask yourself, "what's happening with energy? momentum?" You really need to consider a lens and draw a picture... to be fair, there was a considerable time crunch... However, it's worth remembering that in a time crunch, you STILL shouldn't reach for the answer first.
Have a look at PS#3, posted on the table on the Canvas Homepage under Week 3.

During Class:

We will take data for the group project!
Figure out how you will work together on the project. Who will be the Tracker/Excel expert? Who will manage the project write-up? Who will make sure that you included all the required elements?
Have fun and good luck! There will be a chance to revise the project after the first round of feedback from me. Stay tuned for details after projects are submitted.

Week 2 Wrap-up

How are you feeling about this class? I hope you are settling into the rhythm. Are you feeling challenged? Having fun? Do you notice that you are learning? How do you know? Take a look at this week's learning objectives and rate yourself. Are there any that you feel shaky about? Others you feel confident in? What strategies can you use to improve where you feel it is needed? Let me know if you need help. And lean on your group mates or the reading discussions. Maybe you are not alone. Looking ahead, next week we will finish the projects and bring in vectors more quantitatively.